1. Graphing Equations in Slope-intercept form
4-1 notes for Algebra 1
Graphing Equations in Slope-intercept form

2. Slope-intercept form
𝑦=𝑚𝑥+𝑏 m – the slope of the line b – the y-intercept of the line (where the line crosses the y-axis) (x, y) all the points that lie on the line.

3. Example 1 pg. 216 Write and graph an equation
Write an equation in slope-intercept form of the line with a slope of and a y-intercept of −1. Then graph the equation.

4. Example 1 pg. 216 Write and graph an equation
Write an equation in slope-intercept form of the line with a slope of 1 4 and a y-intercept of −1. Then graph the equation. 𝑦= 1 4 𝑥−1 3 2 1 4 -1

5. Example 2 pg. 217 Graph Linear Equations

6. Example 2 pg. 217 Graph Linear Equations-2 -1 3 4 5 6 7 -3 -4 -5

7. Constant Functions
𝑦=0𝑥+𝑏 or 𝑦=𝑏 These are horizontal lines and will not cross the x-axis.

8. Example 3 pg. 217 Graph Linear Equations

9. Example 3 pg. 217 Graph Linear Equations-4 -3 -2 -1 2 3 4 5 -5 -6
Graph 𝑦=−7

10. Example 4 pg. 218 Write an Equation in Slope-Intercept Form3 2 1 -4 -3 -2 -1 5
A.) 𝑦= 1 2 𝑥+3 B.) 𝑦=2𝑥−3 C.) 𝑦= 1 2 𝑥−3 D.) 𝑦=−2𝑥−3

11. Example 4 pg. 218 Write an Equation in Slope-Intercept Form3 2 1 -4 -3 -2 -1 5
A.) 𝑦= 1 2 𝑥+3 B.) 𝑦=2𝑥−3 C.) 𝑦= 1 2 𝑥−3 D.) 𝑦=−2𝑥−3

12. Example 5 pg. 219 Write and Graph a Linear Equation
HEALTH The ideal maximum heart rate for a 25-year-old exercising to burn fat is 117 beats per minute. For every five years older than 25, that ideal rate drops three beats per minute. 1.) Write a linear equation to find the ideal maximum heart rate for anyone over 25 who is exercising to burn fat. 2.) Graph the equation. 3.) Find the ideal maximum heart rate for a 55-year-old person exercising to burn fat.

13. Example 5 pg. 219 Write and Graph a Linear Equation
HEALTH The ideal maximum heart rate for a 25-year-old exercising to burn fat is 117 beats per minute. For every five years older than 25, that ideal rate drops three beats per minute. 1.) Write a linear equation to find the ideal maximum heart rate for anyone over 25 who is exercising to burn fat. 𝑅=− 3 5 𝑎+117, where R is the ideal maximum heart rate for a 25-year-old and a is the number of years older than 25.

14. Example 5 pg. 219 Write and Graph a Linear Equation
2.) Graph the equation.
Maximum Heart Rate R
117
116
115
114
113
112
111 1 2 3 4 5 6 7 8 a
Years older than 25

15. Example 5 pg. 219 Write and Graph a Linear Equation
HEALTH The ideal maximum heart rate for a 25-year-old exercising to burn fat is 117 beats per minute. For every five years older than 25, that ideal rate drops three beats per minute. 3.) Find the ideal maximum heart rate for a 55-year-old person exercising to burn fat. 99 beats per minute

16. 4-1 pg o, 50, 51, 53-57o, 69-81(x3)